1. Field of the Invention
The present invention relates to a navigation aid or nautical instrument, and, more particularly, pertains to a rate of turn indicator for indicating the rate of turn from a course of travel for a vessel or other like vehicle.
2. Description of Prior Art
One of the most critical problems confronting the shipping industry, particularly tow-boats, is steering a vessel on a straight and true course without swinging or turning from the predetermined course due to forces of nature such as winds, tides, waves, etc.
Prior art gyroscopic instruments have been very expensive. The prior art gyros are usually complex, expensive, electromechanical instruments with numerous mechanical components subject to structural failure in addition to electrical failure. The prior art instruments have included components such as gears, springs, rotors and brushes, centrifugal switches, all of which are subject to failure. Finally, the instruments had circuitry which sparked and could be hazardous in explosive environments. In any event, if the instruments are purchased, after a costly financial outlay by an operator, the installation, subsequent maintenance, and repair are expensive.
The present invention overcomes the disadvantages of prior art by providing a rate of turn indicator having easy visual readout for a steersman of a vessel that a rate of turn or swing is occurring, and yet sensitive and accurate to the rate of turn while eliminating prior art problems due to friction between components.